During fabrication of a semiconductor die, a large number of semiconductor dice are fabricated on a single wafer or other bulk semiconductor substrate. After the components and circuitry associated with each die are fabricated, a so-called dicing operation is performed on the wafer to separate the individual dice from the wafer (e.g., singulate the dice) and from each other. After dicing, the individual dice may be packaged or may be directly mounted to a semiconductor device, such as to a printed circuit board.
Dicing includes sawing along scribe lines through portions of a wafer, termed “streets,” between the dice with a mechanical saw using, for example, a diamond saw blade. Unfortunately, dicing operations often impose significant stress on the semiconductor wafer and may damage the dice as they are singulated. The potential for damage has been exacerbated by the current implementation of dice singulated from extremely thin wafers of, for example, 50 μm or less thickness. For example, the dicing may initiate fractures at the edges of the individual dice, such as at regions proximate scribe lines, during sawing. If the fractures are severe enough, they may propagate through the die and disrupt the integrated circuitry of the die. The fractures may also lead to delamination of materials within the die and may also expose the integrated circuitry of the die to the ambient environment and contaminants (e.g., moisture and ionic contaminants), potentially causing corrosion and undesired oxidation of such material. In some instances, the die or a package associated with the die may fail as a result of one or more of the fractures, the moisture, or the contaminants to which the die is exposed.
To compensate for cracking of the die, in some instances, dice may be formed with a so-called “die ring” (also sometimes referred to in the art as a “seal ring” or a “guard ring”) around peripheral portions thereof surrounding integrated circuitry of the die. The die ring may include materials that are less prone to cracking or delamination when subject to a dicing operation than adjacent materials proximate the periphery of a die. Accordingly, the die rings may help reduce crack propagation from the periphery of the die to the integrated circuit region of the die during or after dicing operations.